donnabread47

How to Replace an Audi G28 Engine Speed Sensor In this video, Charles the humble mechanic demonstrates how to replace the G28 engine speed sensor. The sensor is located near the transmission's edge just above the flywheel gear. It transmits a signal to the ECU via a grey wire (T55/49), then to the tachometer located in the instrument cluster. 1. Engine Speed Sensor The grey wire is situated on the edge of transmission, just above the flywheel ring. This sensor sends an electrical signal through the grey wire to pin T55/49. click here utilizes this information to regulate the flow of fuel, timig and boost. It also sends signals to the G5 Tachometer located in the instrument cluster. The sensor serves as a reference for comparing with the G40 Camshaft Position Sensor. The ecu needs to know when the crankshaft is TDC and where the camshaft is so it can start spark and injectors in the right way. If this sensor fails the ECU will throw a P00160 code which means the Crank Shaft and Intake Camshaft are not in sync and could indicate the chain is stretched or a jump link on the upper timing chain. However, the code won't appear on its own without additional information from other sensors (G4 and G40). Testing is a bit tricky because there are two connector pins, and they have different functions however the best way to test it is by measuring resistance between the sensor and the ECU. If the sensor is operational, it should be reading around 1000 ohms. Check for evidence of coolant or oil in the connector bay if you are experiencing issues with this component. 2. Injectors Yesterday, while accelerating from the highway paytoll at full speed I noticed a significant decrease in power. It was as if the engine had run out of gas. Or, my injectors weren't firing. This morning i pull out the spark plugs. Three were drenched in gazoline, the 4th one was dry. I placed a tissue over each injector hole, and when i turn the engine on without sparks, the 3 with gazoline jump right out. The 4th one stays closed. I checked the ground connection on ECU pins 14/55/30/55/48/55/14/55/48/ I get zero ohm. Therefore, i think the issue is somewhere else. I also tried to reset the PID without success. The car will start if the G28 is disconnected and runs fine when it is plugged in, but still has the intermittent misfire issue at higher RPM. The temperature sensor for coolant (G62) shows the wrong temperature value of that is -49c even after unplugging it. I also noticed that the oil gauge in the cockpit shows 2 bars but the actual pressure is 0. I'm not sure what to do, i believe that i've ruled out everything else. But i am afraid I might have missed something. If anyone has any suggestions, please let me know! TIA! 3. Fuel Pump The fuel pump of the g28 receives signals from the RPM sensor. The GM-style transmitter functions similarly to the G4 sender, and both operate on the 80,100,200, UrS, and RS2 vehicles. It is easy to find the spare in a salvage shop or a parts store. It is simple to test them – simply switch your DMM into resistance mode and determine the distance between pins 1 and 2 (with the bump at the connector end facing up). They must be infinite Ohms. 4. ECU The ECU in our 20vt turbo (3B AAN ABY) engines needs to know both the speed and position of the crankshaft to make decisions regarding timing of fuel injectors, etc. It utilizes a Crank Position Sensor G4 and an Engine Speed Sensor G28 to achieve this. If you have a problem with either of these sensors, the diagnostic scanner will show the codes that could trigger the engine shutting down. A failing G28 sensor can cause an inaccurate speed counter for your gearbox or a gearbox that shifts faster than normal, and/or a misfire in the gear. It is probable that your sensor is failing and needs to be replaced if you experience any of these symptoms. They're inexpensive and easy to locate especially in the case of an Bosch model like ours. Alternately, GM's version this part is an excellent choice. 5. Tachometer A malfunctioning engine sensor can cause a number of problems in your vehicle. It is an important part of the transmission in your Audi because it relays information to the ECU on how fast or slowly the engine of the car is spinning. This sensor can cause the transmission to malfunction and other components in the car to be affected. The G5 engine sensor is located at the edge of the transmission, just above the flywheel ring. It transmits a signal via gray wire to ECU pin T55/49. spare audi key uses this signal to regulate fuel and boost, as well as timig. It also transmits it to the G5 Tachometer located in the instrument cluster. You can test for sensor failure by examining the continuity from the sensor to the tachometer. Additionally, you can check continuity between pin T55/49 of the ECU and pin T6a/1 of the instrument cluster (trace [79]) and between pin T6a/1 and pin T26a/12. It should show approximately 1000 ohms resistance between those points. This is the same across the Audi 80-100-200-RS2 range, from the 1985 MC all the way up to the 1997 UrS An and 1995 RS2 DU, so you might find good ones in wrecking yards.